Inflammation is a biological response of the horse's body to harmful stimuli, such as pathogens, damaged cells, or irritants. It is a complex process that involves the activation of immune cells, the release of inflammatory mediators, and changes in blood flow. In horses, inflammation can manifest in various forms, affecting different tissues and organs, including the joints, respiratory system, and skin. The inflammatory response is an essential component of the horse's immune system, aiming to eliminate the initial cause of cell injury, clear out damaged cells and tissues, and establish tissue repair. This topic page gathers peer-reviewed research studies and scholarly articles that explore the mechanisms, effects, and management of inflammation in equine health.
Portus BJ, Reilas T, Katila T.There is conflicting evidence over the role seminal plasma plays in sperm transport and inflammation within the uterus of mares. In in vitro studies, seminal plasma has been shown to reduce polymorphonuclear neutrophil (PMN) function, but the opposite effect on uterine inflammation has been reported in vivo. Objective: To study the effect of seminal plasma on uterine contractility, inflammation and pregnancy rates by inseminating mares with low doses of sperm free from seminal plasma (Group 1) and containing seminal plasma (Group 2). Methods: Synchronised mares were inseminated with 50 x 10(6)...
Trumble TN.In horses, lameness is often attributable to some degree of osteoarthritis (OA), a complex disease process that is highlighted by eventual degradation of articular cartilage. Conventional therapies for OA in horses are designed to relieve pain and discomfort and often include pharmacologic intervention with nonsteroidal anti-inflammatory drugs or intra-articular steroids. Oral administration of nutraceutical products to the horse is common and easy and is perceived to be a benign treatment for OA in horses. The main goal for use of nutraceuticals is to use them in OA cases to attempt to lower ...
Porter M.The principles of physical rehabilitation therapy can be applied to the horse to provide a reduction in discomfort and dysfunction associated with the various forms of joint disease. Physical agents,such as ice, heat, electricity, sound, light, magnetic fields, compression, and movement, can be used by the rehabilitation therapist to attempt to control pain, reduce swelling, and restore optimal movement and function in the affected joint. The equine therapist's attention is focused not only on the affected joint but on the body as a whole to manage secondary or compensatory problems.
Jacobsen S, Jensen JC, Frei S, Jensen AL, Thoefner MB.Early recognition of excessive inflammation and infectious complications after surgery, leading to early institution of therapy, reduces post operative discomfort and facilitates recovery. Because serum amyloid A (SAA) is a highly sensitive marker of inflammation, measurements of SAA and other acute phase reactants in the equine surgical patient may be valuable in assisting clinical assessment of post operative inflammation. Objective: To investigate changes in inflammatory markers after castration and to correlate levels of acute phase reactants with clinical severity of inflammation after ca...
Fortier LA.Systemic therapies for joint disease may be prescribed when a single joint is involved or when multiple sites are affected. The precise therapeutic regimen recommended depends on the duration,cause, and site(s) of injury and is often an adjunct to intra-articular or supportive therapies. If the clinical signs of joint disease are acute and moderate in severity, nonsteroidal anti-inflammatory drugs are often administered to alleviate pain and inflammation. When aiming for more of a generalized maintenance or chondro-protective regimen, an alternative medication, such as hyaluronan,polysulfated ...
Mancini DA, Mendonça RM, Dias AL, Mendonça RZ, Pinto JR.Trypsin is required in the hemagglutinin (HA) cleavage to in vitro influenza viruses activation. This HA cleavage is necessary for virus cell entry by receptor-mediated endocytosis. Bacteria in the respiratory tract are potential sources of proteases that could contribute to the cleavage of influenza virus in vivo. From 47 samples collected from horses, pigs, and from humans, influenza presence was confirmed in 13 and these samples demonstrated co-infection of influenza with flagellated bacteria, Stenotrophomonas maltophilia from the beginning of the experiments. Despite treatment with antibio...
Hurley DJ, Parks RJ, Reber AJ, Donovan DC, Okinaga T, Vandenplas ML, Peroni JF, Moore JN.Administration of black walnut heartwood extract (BWHE) via nasogastric tube induces acute laminitis in horses. However, the processes responsible for the development of laminitis, including laminitis induced with BWHE, remain unclear. The results of recent studies indicate that administration of BWHE initiates an inflammatory response in the laminar tissues and that this response may be due to extravasation of activated leukocytes from the circulation. This study examines the effects of BWHE administration on the dynamics of circulating neutrophils and monocytes, and the capacity of blood leu...
Ishihara A, Bertone AL, Rajala-Schultz PJ.To evaluate the association between subjective lameness grades and kinetic gait parameters and assess the variability in kinetic parameters in horses with experimentally induced forelimb lameness. Methods: 32 horses. Methods: Forelimb lameness was induced in each horse via injection of lipopolysaccharide into 1 metacarpophalangeal joint (40 experimental trials). Subjective lameness grading and 13 kinetic gait parameters (force plate analysis) were assessed before (baseline) and at 12, 18, and 24 hours after lipopolysaccharide injection. While horses were trotting, kinetic gait analysis was per...
Hosaka Y, Kirisawa R, Ueda H, Yamaguchi M, Takehana K.Tumor necrosis factor (TNF) receptors (TNF-R)-mediated cell survival or apoptosis has been demonstrated in many cells, but little is known about survival or apoptotic signals via TNF-R1 in tendinocytes. In this study, we focused on four signaling factors, TNFalpha, TNF-R1, TNFR-associated factor2 (TRAF2) and caspase-3, in order to elucidate the signaling events in tendinocytes. Samples were obtained from normal, inflamed and scar-formed equine superficial digital flexor tendons. To detect these signaling factors, samples were subjected to immunohistochemistry and Western blot analysis, and som...
Pusterla N, Holmberg TA, Lorenzo-Figueras M, Wong A, Wilson WD.A 10-year-old Thoroughbred gelding was admitted to the Veterinary Medical Teaching Hospital of the University of California-Davis with a 2-week history of intermittent fever and acute onset of lethargy, anorexia, and ataxia. Although the clinical signs were nonspecific, the results of initial hematologic and biochemical analysis were consistent with a chronic inflammatory process. Thoracic radiographs revealed an increased fine reticulonodular interstitial opacity throughout the dorsal caudal lung fields. Cytologic examination of bronchoalveolar lavage (BAL) fluid showed mixed inflammation wit...
Stokol T, Erb HN, De Wilde L, Tornquist SJ, Brooks M.Fibrin(ogen) degradation products (FDPs) and D-dimer are sensitive indicators of excessive fibrinolysis due to disseminated intravascular coagulation (DIC) in dogs. To the authors' knowledge, latex-agglutination-based plasma FDP and D-dimer assays have not been validated for use in horses. Objective: To determine: 1) sensitivity and specificity of latex agglutination serum and plasma FDP and D-dimer assays for diagnosis of DIC; and 2) their prognostic value in horses with severe colic. Methods: At hospital admission and 24 hours later, blood was collected from 30 healthy horses and 20 horses w...
Sinnemaa L, Järvimaa T, Lehmonen N, Mäkelä O, Reilas T, Sankari S, Katila T.The effect of artificial insemination (AI) volume on uterine contractility and inflammation and on elimination of semen in the reproductive tract of mares was examined for 4 h after AI using two methods, scintigraphy and ultrasonography. The same doses were used in both methods: 2 and 100 ml of skim milk-extended frozen semen. In the scintigraphic study, the number of reproductively normal mares was four per group and in the ultrasonographic study five per group. For scintigraphy, the semen was radiolabelled with technetium-99m. The static scintigrams were acquired immediately before and 30, 6...
Vandenplas ML, Moore JN, Barton MH, Roussel AJ, Cohen ND.To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data. Methods: 765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals. Methods: Serum concentrations of SAA and LBP were determined by immunoturbidometric and dot-blot assays, r...
Munsterman AS, Bertone AL, Zachos TA, Weisbrode SE.To determine the effects of pretreatment with alpha-linolenic acid, an omega-3 polyunsaturated fatty acid, on equine synovial explants challenged with lipopolysaccharide (LPS). Methods: 8 mature mixed-breed horses (4 mares and 4 geldings). Methods: Synovial explants were assigned to receive 1 of 7 concentrations of alpha-linolenic acid, ranging from 0 to 300 microg/mL. At each concentration, half of the explants were controls and half were challenged with 0.003 microg of LPS as a model of synovial inflammation. Cell inflammatory response was evaluated by measurement of prostaglandin E2 product...
Laan TT, Bull S, Pirie RS, Fink-Gremmels J.To evaluate cytokine production by equine alveolar macrophages after exposure to lipopolysaccharide (LPS), Aspergillus fumigatus, and hay dust, and determine the effect of clenbuterol on the cytokine response. Methods: 6 horses. Methods: Alveolar macrophages were exposed to PBS solution (negative control), LPS, hyphae and conidia of Aspergillus fumigatus (AF), or a suspension of hay dust (HDS) and incubated for 24 hours at 37 degrees C. Concentrations of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta were measured in the supernatant. The procedure was repeated with cells that wer...
Mills PC, Cross SE.Commercial formulations of non-steroidal anti-inflammatory drugs (NSAIDs) are developed for human use but the extent to which they will pass through equine skin is unknown. Skin was harvested from five Thoroughbred geldings from the thorax, groin and leg (dorsal metacarpal) regions and frozen (-20 degrees C) until required. Two grams of methylsalicylate (MeSa) gel was applied to defrosted full-thickness samples in diffusion cells and the penetration of MeSa and its active metabolite, salicylate (Sa), through skin samples were measured over 24 h. Significantly higher (P < or = 0.02) total sa...
Brünott A, van der Velden MA.In this case report a 20-year-old horse with unilateral eosinophilic keratitis is presented. The occurrence, clinical symptoms, histological findings and treatment of this ocular disorder are described and discussed against the background of relevant literature. Local administration of 0.1% dexamethason was successful.
Busoni V, Heimann M, Trenteseaux J, Snaps F, Dondelinger RF.We describe the abnormal magnetic resonance (MR) imaging findings in the deep digital flexor tendon (DDFT) and distal sesamoid bone in horses with radiographic changes compatible with navicular syndrome. Thirteen postmortem specimens were examined using a 1.5-T magnetic field, with spin echo (SE) T1-weighted, turbo SE (TSE) proton density-weighted (with and without fat saturation), and fat saturation TSE T2-weighted sequences. The limbs were then dissected to compare the MR findings with the gross assessment and histologic examination of the DDFT and distal sesamoid bones. Tendonous abnormalit...
Gehlen H, Ohnesorge B.To describe removal of guttural pouch chondroids through a laser fenestrated mesial septum in a pony with an obstructed pharyngeal ostium of the left guttural pouch. Methods: Case report. Methods: Pony. Methods: Transendoscopic laser neodymium:yttrium aluminum garnet (Nd:YAG) fenestration of the mesial guttural pouch septum was made by contact method (bare fiber, 15-25 W, exposure time 4 seconds). Dissected tissue was removed by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and multiple chondroids of varying size were removed from the left guttural pouch through the ...
Deaton CM, Marlin DJ, Smith NC, Harris PA, Dagleish MP, Schroter RC, Kelly FJ.Effects of acute airway inflammation induced by organic dust inhalation on pulmonary antioxidant status were investigated in healthy horses and horses affected by recurrent airway obstruction. Exposure to organic dust induced acute airway neutrophilia, which was associated with increases in elastase and decreases in ascorbic acid concentrations in bronchoalveolar lavage fluid. However, markers of oxidative stress were unaffected, as was hydrogen peroxide in breath condensate. Decreases in ascorbic acid correlated with increased respiratory resistance (P = .001) when both groups were combined. ...
Causey RC.Equine uterine infections inflict major losses on the equine industry. Persistent inflammation of the oviduct and uterus leads to loss of the conceptus and mares susceptible to infection have weakened uterine defences partly due to retention of inflammatory exudate. Bacteria may trigger inflammation, resist phagocytosis, or adhere to the endometrium and types of infection range from genital commensals in susceptible mares to reproductive pathogens in normal mares. Uterine infections are diagnosed by history, detection of uterine inflammation, and isolation of typical organisms and susceptible ...
Wyse CA, Skeldon K, Hotchkiss JW, Gibson G, Yam PS, Christley RM, Preston T, Cumming DR, Padgett M, Cooper JC, Love S.The aim of this study was to assess the effects of changes to the stable environment on exhaled markers of respiratory inflammation in six horses with clinical histories of recurrent airway obstruction. The horses were maintained for two weeks under conventional stable management (straw bedding and hay) and for two weeks on a reduced-dust regimen (paper bedding and ensiled grass), in a crossover study design. Exhaled ethane and carbon monoxide (CO) and exhaled breath condensate hydrogen peroxide (H(2)O(2)) were measured every three days under each regimen. The presence of clinical signs of air...
Desrochers AM, Dolente BA, Roy MF, Boston R, Carlisle S.To evaluate the viability of Saccharomyces boulardii after PO administration in clinically normal horses and its efficacy as a treatment for horses with acute enterocolitis. Methods: Prospective study. Methods: 5 clinically normal horses and 14 horses with acute enterocolitis. Methods: Feces were collected from 5 clinically normal horses and submitted for microbial culture for 2 days prior to administration of a lyophilized form of S. boulardii (25 or 50 g, PO, q 12 h) for 10 days. Feces were collected for microbial culture 5 and 10 days after treament initiation and 10 days after treatment wa...
Lepault E, Céleste C, Doré M, Martineau D, Theoret CL.Wound repair in horse limbs is often complicated by exuberant granulation tissue, a condition characterized by excessive fibroplasia and scarring and that resembles hypertrophic scars and keloids in man. The aim of this study was to compare microvascular occlusion and apoptosis in wounds of the limb with those of the body, which heal normally. Five 6.25 cm(2) wounds were created on both forelimbs and on the body of six horses. One limb was bandaged to stimulate excessive fibroplasia. Weekly biopsies were evaluated histologically and immunohistochemically for mutant p53 protein by terminal deox...
Wong DM, Buechner-Maxwell VA, Manning TO, Ward DL.To evaluate the precision of intradermal testing (IDT) in horses. Methods: 12 healthy adult horses. Methods: IDT was performed on the neck of each horse by use of 2 positive control substances (histamine and phytohemagglutinin [PHA]) and a negative control substance. An equal volume (0.1 mL) for each injection was prepared to yield a total of 20 syringes ([4 concentrations of each positive control substance plus 1 negative control substance] times 2 positive control substances times 2 duplicative tests) for each side of the neck. Both sides of the neck were used for IDT; therefore, 40 syringes...
Wong DM, Buechner-Maxwell VA, Manning TO, Ward DL.To evaluate differences in response to ID injection of histamine, phytohemagglutinin (PHA), and Aspergillus organisms between clinically normal horses and horses with recurrent airway obstruction (RAO). Methods: 5 healthy adult horses and 5 adult horses with RAO. Methods: Intradermal testing (IDT) was performed on the neck with 2 positive control substances (histamine and PHA) and a mixture comprising 5 Aspergillus species. Four concentrations of each test substance plus a negative control substance were used. Equal volumes (0.1 mL) of each test substance were prepared to yield 15 syringes ([4...
Simonen-Jokinen T, Maisi P, Tervahartiala T, McGorum B, Pirie S, Sorsa T.Matrix metalloproteinases (MMPs) are involved in tissue destruction in allergic airway diseases. We studied the ability of various allergenic substances to directly activate recombinant 92kDa proMMP-9. The substances included hay dust suspension (HDS) and its components (supernatant, particulate matter and wash fluid of particulate matter), storage mite extract and two Aspergillus fumigatus extracts. The allergen suspensions were incubated in vitro with proMMP-9. After incubation the conversion of proMMP-9 to 10kDa lower active forms were studied using gelatin zymography and Western immunoblot...
Black SJ, Lunn DP, Yin C, Hwang M, Lenz SD, Belknap JK.The mechanisms that initiate the pathophysiologic changes in the digital laminae in equine laminitis are poorly understood. Due to the fact that (1) the horse at risk of laminitis has many similarities clinically to the human sepsis patient and (2) our recent finding of marked laminar proinflammatory cytokine expression at the developmental time point of the black walnut extract (BWE) model of laminitis, we tested the possibility that, similar to organ damage in human sepsis, leukocyte emigration is an early event in laminitis. Using immunoperoxidase methods with an anti-equine CD13 monoclonal...
Tennent-Brown BS.Blood lactate concentration can be easily measured by practitioners using inexpensive point-of-care meters. Anaerobic tissue metabolism resulting from inadequate oxygen delivery (DO2) is the most important cause of an increase in blood lactate concentration in equine patients. However,hyperlactatemia also occurs under conditions of apparently adequate DO2, usually in association with sepsis and an intense inflammatory reaction. Numerous mechanisms have been proposed for aerobic hyperlactatemia, including increased Na+/K+-ATPase activity in response to inflammatory mediators; inhibition of pyru...
Brink P, Skydsgaard M, Teige J, Tverdal A, Dolvik NI.To develop a scoring system for histopathologic changes in the synovium of tarsocrural joints (TCJs) of horses with osteochondritis dissecans (OCD) and to test for association between histopathologic changes and joint effusion or lameness. Methods: 93 horses with OCD of the intermediate ridge of the tibia of 1 or both TCJs (134 joints) and 38 control horses without disease of TCJs (38 joints). Methods: For OCD-affected horses, pretreatment lameness, TCJ effusion, and results of pelvic limb flexion test were scored. Synovial biopsy specimens were obtained from TCJs of OCD-affected horses during...
Grages AM, Verhaar N, Pfarrer C, Breves G, Burmester M, Neudeck S, Kästner S.In experimental studies investigating strangulating intestinal lesions in horses, different ischaemia models have been used with diverging results. Therefore, the aim was to comparatively describe ischaemia reperfusion injury (IRI) in a low flow (LF) and no flow (NF) model. Under general anaesthesia, 120 min of jejunal ischaemia followed by 120 min of reperfusion was induced in 14 warmbloods. During ischaemia, blood flow was reduced by 80% (LF, n = 7) or by 100% (NF, n = 7). Intestinal blood flow and oxygen saturation were measured by Laser Doppler fluxmetry and spectrophotometry. Clinical, hi...
Nourian AR, Baldwin GI, van Eps AW, Pollitt CC.The pathology of equine laminitis has been well-documented 48 h after dosing with oligofructose when clinical lameness and lamellar disintegration is well advanced. Further analysis of the earliest lesions, by collecting lamellar samples at the first sign of foot lameness after oligofructose dosing is required in order to increase understanding of the disease. Objective: To investigate lamellar epidermal hemidesmosome damage and basement membrane dysadhesion by transmission electron microscopy (TEM). Methods: Eight clinically normal, mature Standardbred horses were divided randomly into 2 grou...
Beghelli D, Zallocco L, Angeloni C, Bistoni O, Ronci M, Cavallucci C, Mazzoni MR, Nuccitelli A, Catalano C, Hrelia S, L쫌hini A, Giusti L.Intense exercise can cause inflammation and oxidative stress due to the production of reactive oxygen species. These pathophysiological processes are interdependent, and each one can induce the other, creating a vicious circle. A placebo-controlled blind study was carried out in show jumping horses (n. 16) to evaluate the effects of a commercial dietary supplement (Dolhorse® N.B.F. Lanes srl, Milan, Italy) containing Verbascum thapsus leaf powder (1.42%), Curcuma longa (14.280 mg/kg), and Boswellia serrata (Roxb ex Colebr) (14.280 mg/kg) extracts. Before and after 10 days of dietary supplemen...
Schoster A, Altermatt N, Torgerson PR, Bischofberger AS.To describe outcome and complications after large intestinal trocarization in equids with colic and identify factors associated with nonsurvival and clinically relevant peritonitis (CRP). Methods: 228 (198 horses, 24 ponies, and 6 donkeys and mules) equids with colic that underwent large intestinal trocarization. Methods: Medical records from 2004 through 2015 were reviewed for equids with colic that underwent large intestinal trocarization. Factors associated with nonsurvival in all (ie, surgically and medically treated) equids and with CRP in medically only treated equids were identified. Me...
Cohen JM, Southwood LL, Engiles J, Leitch M, Nunamaker DM.To examine the efficacy and biocompatibility of a thiolated gelatin-thiolated carboxymethyl hyaluronan (CMHA-SGX) sponge as an osteoconductive device in an equine second and fourth metacarpal bone defect model. Methods: Seven millimetre segmental ostectomies were created bilaterally in the second and fourth metacarpal bones of four horses. The left and right metacarpal defects were randomly assigned to (1) be filled with a CMHA-SGX sponge (treated) or (2) were left unfilled (control). The duration of the study was nine weeks. Bone healing was evaluated using serial radiology, as well as histol...
Rosa MVD, Rosa M, Botteon PTL.This study aimed to evaluate the use of equine amniotic membrane (EAM), frozen indirectly using liquid nitrogen and stored between -10° and -24°C, in the treatment of equine skin lesions. Six healthy female horses, aged 3-10 years, were included in this study. EAM was collected from previously evaluated healthy parturient mares. Wounds were surgically created at the distal ends of the forelimbs. One limb was chosen for treatment, and the contralateral limb was chosen as the control. Pain sensitivity, presence of granulation tissue, secretions, and bleeding after debridement during cleaning w...
Galey FD, Whiteley HE, Goetz TE, Kuenstler AR, Davis CA, Beasley VR.Twelve light horse geldings developed laminitis within 8 to 12 h of being dosed by nasogastric tube with an aqueous extract of black walnut (Juglans nigra). Four of the 12 horses developed the severe signs of grade 3 laminitis (lame at a walk, refused to lift feet). Laminitis was accompanied by mild depression and limb oedema. There was no evidence of shock or colic. The horses developed neutropenia by 4 h after dosing with the extract, which shifted to a relative neutrophilia by 8 to 12 h. Minimal increases in plasma epinephrine and cortisol concentrations were suggested in severely affected ...
Boivin R, Vargas A, Cano P, Lavoie JP.Recurrent inflammation in severe equine asthma causes a remodeling of the airways leading to incompletely reversible airway obstruction. Despite the improvement of clinical signs and lung function with glucocorticoids (GC), inflammation, translated by an increased percentage of neutrophils, persists in the airways. Regulatory T cells (Treg) have been shown to have anti-inflammatory properties and play an important role in balancing the immune response by suppressing effector lymphocyte activity. However, interactions between Treg, neutrophils and glucocorticosteroids in vivo are unclear, parti...
Kimura S, McCoy AM, Boothe DM, Wooldridge AA, Graff E, Hammack SM, Cresci L, Hofmeister E, Lascola KM.To describe misoprostol pharmacokinetics and anti-inflammatory efficacy when administered orally or per rectum in endotoxin-challenged horses. Methods: 6 healthy geldings. Methods: A randomized 3-treatment crossover design was performed with a minimum washout period of 28 days between treatment arms. Prior to endotoxin challenge (lipopolysaccharide, 30 ng/kg IV over 30 minutes), horses received misoprostol (5 µg/kg once) per os (M-PO) or per rectum (M-PR) or water as control (CON). Clinical parameters were evaluated and blood samples obtained to measure plasma misoprostol free acid concentrat...
Millares-Ramirez EM, Picotte K, Lavoie JP.Intra-articular (IA) administration of corticosteroids is performed routinely in equine practice. The lung function of severe asthmatic horses has recently been shown to be improved by IA triamcinolone acetonide (TA). We therefore hypothesised that IA methylprednisolone acetate (MPA), another commonly used corticosteroids, would also decrease the airway obstruction in severe asthmatic horses. Objective: To compare the effects of intra-articular (IA) and intramuscular (IM) methylprednisolone acetate (MPA) administration on lung function and serum cortisol levels in horses with severe asthma. Me...
Hanie EA, Sullins KE, Powers BE, Nelson PR.The effect of lesion depth on the quality of third carpal bone cartilage repair was examined. A 1-cm diameter articular defect penetrating the calcified cartilage in one limb and the subchondral bone plate in the opposite limb was created in the radial facet of the third carpal bones. Clinical and xeroradiographic examinations were performed every 4 weeks until 4 months (3 horses) and 6 months (3 horses) after surgery. The synovial membrane, non-opposing articular surfaces and articular defects were examined grossly, histologically and histochemically. Grossly, deeper defects contained thicker...
Roquet I, Hendrick S, Carmalt JL.Based on a systemic complete blood count and a synovial fluid sample, to develop a mathematical model enabling the approximation of corrected values for synovial fluid white blood cell (WBC) count, neutrophil percentage, and total protein concentration in samples of synovial fluid that were contaminated by blood. Methods: Peripheral venous blood and synovial fluid samples were obtained from ten horses. A pooled synovial fluid sample from each horse was separated into 2 mL aliquots, which were subsequently contaminated with a known percentage of autogenous blood (0 to 50% of the synovial fluid ...
de la Rebière de Pouyade G, Serteyn D, Deby-Dupont G, Franck T.Neutrophil myeloperoxidase (MPO) and elastase can be released in severe inflammatory diseases and cause tissue injuries. Equine enzymes have already been individually purified from large blood quantities. We describe the isolation of both enzymes from a same limited blood volume. Both MPO and elastase were extracted by crushing PMN isolated by centrifugation on a percoll-gradient from a 460 ml blood collection. MPO and elastase were separated by an ionic exchange chromatography phase and further purified by gel filtration chromatography on Superdex 200 and 75, respectively. Enzymes were identi...
Boudreaux MK, Koehler J, Habecker PL, Del Piero F.Exercise-induced pulmonary hemorrhage (EIPH) is a common disorder of equine athletes. The role of polymorphisms in genes encoding hemostasis-regulatory proteins in horses with abnormal hemorrhage is unknown. Objective: The goal of this study was to evaluate the genes encoding 2 ectonucleotidases, CD39/NTPDase-1 and CD39L1/NTPDase-2, and one ecto-5' nucleotidase, CD73, in horses with abnormal hemorrhage or pathologic changes consistent with EIPH. Methods: Twenty-three horses with histories of abnormal hemorrhage, 8 horses with gastrointestinal signs, and 45 healthy horses were evaluated using p...
Aristizabal FA, Lopes MA, Silva A, Avanza MF, Nieto JE.To evaluate the effect of onlay mesenteric flaps (MFs) with end-to-end jejunojejunostomy on stomal diameter, length of jejunum with reduced stomal diameter, abdominal adhesion formation, and healing. Methods: Experimental study. Methods: Healthy adult horses (n = 6). Methods: Two hand sewn end-to-end jejunal anastomoses using a 1 layer simple continuous serosubmucosal suture pattern were performed in each horse ∼ 2 and 5 m oral to the ileocecal fold. Using a random design for selection anastomosis location (oral or aboral), 1 anastomosis was covered with 2 adjacent onlay MFs secured with int...
Ross MW, Orsini JA, Richardson DW, Martin BB.Infectious arthritis of the tarsocrural joint was treated in 13 horses with closed suction drainage through a flat, fenestrated, latex (Jackson-Pratt) drain, broad-spectrum antimicrobial agents, nonsteroidal anti-inflammatory drugs, and bandage immobilization. In 11 horses, arthroscopic lavage and debridement were also performed. Ingress drains were placed for lavage in six horses. Ten horses returned to their previous level of competition or were sound. One horse raced but had lameness of the affected tarsocrural joint and dropped in racing class; one horse was euthanatized because of laminit...
Pezzanite LM, Hendrickson DA, Dow S, Stoneback J, Chow L, Krause D, Goodrich L.Antibiotics have been injected intra-articularly by equine veterinarians for decades, either prophylactically when other drugs are administered for osteoarthritis or therapeutically to treat septic arthritis. This route of administration has also more recently gained attention in human orthopaedic clinical practice, particularly as an alternative to systemic antibiotic administration to treat infections following prosthetic arthroplasty. While the rationale for injecting antibiotics intra-articularly has been largely focused on achieving high local drug concentrations, there has been relativel...
Dagleish MP, Brazil TJ, Scudamore CL.Lipopolysaccharide (LPS) and N-formyl-methionyl-leucyl-phenylalanine (fMLP)-like peptides are Gram-negative bacterial cell wall components which, when released into the peripheral circulation in endotoxaemia, have the potential to activate leucocytes. In vitro, equine neutrophils require priming with LPS in order to generate reactive oxygen intermediates (ROI) in response to fMLP. Objective: The aim of this study was to examine whether the release of other neutrophil products is similarly dependent on prior priming with LPS. In particular, neutrophil elastase (NE), a potent proteolytic enzyme,...
Wilkołek P, Sitkowski W, Szczepanik M, Adamek Ł, Pluta M, Taszkun I, Gołyński M, Malinowska A.Allergic responses in humans, horses and other species are mediated by immunoglobulin E (IgE) antibodies. Serum testing to detect allergen-specific IgE antibodies has been developed for dogs, cats and horses; this allows for the identification of allergens and determination of appropriate allergen- specific immunotherapies. This study compared serum allergen-specific IgE concentrations in atopic and healthy horses. The study was performed on Malopolski breed atopic (n=21) and nonatopic (n=21) clinically healthy horses. Allergen-specific IgE serum concentrations were measured in summer seasons ...
Venugopal CS, Holmes EP, Koch CE, Curtis LA, Holm AS, Moore RM.To evaluate the effectiveness of 2 potential endothelin (ET)-1 antagonists in blocking the contractile responses of equine colonic vessels to increasing concentrations of ET-1. Methods: Mesenteric vessels from 6 clinically healthy horses. Methods: Colonic vessels (arterial and venous rings) were placed in organ baths with oxygenated Tyrode solution at 37 C. Each was attached to a force transducer interfaced with a polygraph, and 2 g of tension was applied and equilibrated for 45 minutes. Then, B-1 (PD 142893) and B-2 (PD 145065) ET-1 antagonists were tested. One ring from each vessel type was ...
Benamou AE, Art T, Marlin DJ, Roberts CA, Lekeux P.Chronic obstructive pulmonary disease (COPD) represents a major cause of loss of performance in the horse. The role of endothelin (ET), a potent bronchoconstrictive and vasoactive peptide, is currently being investigated in asthma and other obstructive respiratory diseases in man. We have previously found elevated systemic and pulmonary endothelin levels in horses during exacerbation of COPD. In the present study, our aim was to examine possible variations in ET concentrations occurring during exercise in COPD horses. We compared the effects of intense treadmill exercise on the recovery of end...
Henríquez C, Morán G, Carrasco C, Sarmiento J, Barría M, Folch H, Uberti B.It is accepted that T regulatory cells (Treg) control different types of immune responses. In connection with this role, we have recently described an important increase in CD4+, CD25, Foxp3+ lymphocytes in the airway system of horses coursing with an exacerbation of severe equine asthma (EA). To explore the potential role of this population in the resolution of EA inflammation, we used a murine experimental model in which airway neutrophilic inflammation, which is similar to that observed in EA, is induced in mice by continual exposure to Aspergillus fumigatus contaminated hay. This model has...
Caron JP, Fretz PB, Bailey JV, Barber SM, Hurtig MB.Epistaxis, caused by guttural pouch mycosis, was treated by balloon-tipped catheter and ligature occlusion of the involved arteries in 13 horses. In 7 horses, more than one artery was catheterized. Serious postoperative hemorrhage was prevented in all horses. Long-term endoscopic follow-up examination was possible in 8 horses, and all had complete regression of the fungal lesion as early as 5 weeks after surgery. Six of the 8 horses did not receive medical treatment. Problems related to the use of the balloon-tipped catheter technique were rare. There were incisional infections in 3 horses, ca...
Hood DM, Stephens KA, Bowen MJ.Phenoxybenzamine, an alpha adrenergic antagonist, was administered IV to 6 clinically normal horses, 5 horses with experimentally induced diarrhea, and 7 horses with naturally-occurring diarrhea. It was established that a total of 2 mg of phenoxybenzamine/kg of body weight given in divided doses resulted in alpha adrenergic blockage of approximately 72 hours' duration, tranquilization, and mild constipation in the normal horse. The 5 experimental cases of diarrhea were involved in a laminitis research protocol in which laminitis was induced by oral carbohydrate overload. In all 5 of those case...
Ewart SL, Robinson NE.This review highlights the critical importance of phenotype definition in the understanding of the pathogenesis of respiratory disease in horses. The general approach to genetic studies is discussed and comparative studies of recurrent airway obstruction (RAO) conditions, such as asthma, described in the context of learning more about equivalent equine conditions. The availability of methods to study genetic tests have previously relied on DNA sequence knowledge from man, laboratory and domesticated animals, but recent data from the horse genome sequence are now available. This should facilita...
Grimm AL, Schoon HA, Schöniger S.Equine endometritis eosinophilica (EE) is rarely described and its diagnostic criteria are not defined. The aim of this study was to characterize histological features of EE. A data base (1995-2013) was searched for biopsies with increased eosinophils. This study included all biopsies with this diagnosis and representative biopsies without this record. The definition of equine EE was based on criteria for EE in women and the results of the determination of physiological numbers of eosinophils within the equine endometrium. EE was diagnosed in 55 mares. Biopsies of 10 mares contained eosinophil...
McEntee MF.Thirty equine cutaneous mastocytomas were examined histologically and two were studied ultrastructurally. Lesions were characterized by distinct sheets of well-differentiated mast cells with variable degrees of eosinophil infiltration, collagen degeneration, necrosis, granulomatous inflammation and fibrosis. Twenty-two of 25 growths did not recur for up to 6 years after surgical excision, two recurred at the surgical site and one spontaneously regressed less than 3 months after obtaining a biopsy sample. Equine cutaneous mastocytoma is a benign proliferative lesion which seldom recurs after ex...
Hoffman CJ, McKenzie HC, Furr MO, Desrochers A.Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis occurs in horses with systemic inflammatory response syndrome (SIRS). Peripheral resistance to glucocorticoids has not been investigated in horses. Objective: To determine if glucocorticoid receptor (GR) function in horses can be measured using flow cytometry, and to use this information to evaluate HPA axis dynamics. Methods: Eleven healthy adult horses in parts 1 and 2. Ten horses with SIRS and 10 age and sex matched controls in part 3. Methods: Flow cytometry was used to evaluate GR density and binding affinity (BA) in 3 healthy...
